Method and apparatus for processing inorganic acidic gas

Abstract

A method for treating waste gas containing inorganic acid is disclosed. The method includes the following steps: (a) forming a mixture of inorganic acidic gas and a nebulized alkaline solution wherein the nebulized alkaline solution can be produced continuously or periodically; (b) forcing the mixture to pass through an adsorbent bed; and (c) releasing the treated gas. An apparatus for treating the inorganic acid gas with the method illustrated above is also disclosed here. The method can regenerate poisoned adsorbents online, and save time, space and cost simultaneously.

1 . A regenerative method of adsorbent for processing inorganic acidic gas, comprising the following steps: 
 (a) washing an adsorbent with a washing solution; and    (b) spraying or immersing a nebulized alkaline solution to the said adsorbent.    
     
     
         2 . The regenerative method as claimed in  claim 1 , wherein the washing solution is de-ionized water, pure water processed by reverse osmosis, distilled water, tap water, or a mixed solution of any two of the aforementioned waters.  
     
     
         3 . The regenerative method as claimed in  claim 1 , wherein the said alkaline solution is potassium hydroxide solution, sodium hydroxide solution or their mixture.  
     
     
         4 . The regenerative method as claimed in  claim 1 , wherein the said adsorbent is spherical active carbon, granular active carbon, pulverized active carbon, active carbon fabric, zeolite adsorbent, or mixtures of any of the two aforementioned materials with adsorbability.  
     
     
         5 . A regenerative de-acid apparatus for inorganic acidic gas, comprising: 
 a tank having an gas inlet and an exhaust outlet;    at least one adsorbent bed having one adsorbent, wherein the adsorbent bed is received inside the tank;    at least one alkaline solution supply unit placed inside the tank and providing at least one alkaline solution to the at least one adsorbent bed; and    at least one washing solution supply unit, positioned inside the tank and providing a solution for washing the said at least one adsorbent; wherein the alkaline solution supply unit is placed between the adsorbent bed and the gas inlet.    
     
     
         6 . The regenerative de-acid apparatus for inorganic acidic gas as claimed in  claim 5 , wherein the alkaline solution is potassium hydroxide solution, sodium hydroxide solution or their mixture.  
     
     
         7 . The regenerative de-acid apparatus for inorganic acidic gas as claimed in  claim 5 , wherein the said at least one adsorbent is spherical active carbon, granular active carbon, pulverized active carbon, active carbon fabric, zeolite adsorbent, or mixtures of any two of the aforementioned materials with adsorbability.  
     
     
         8 . The regenerative de-acid apparatus for inorganic acidic gas as claimed in  claim 5 , wherein the thickness of the said at least one adsorbent is 1 cm to 60 cm.  
     
     
         9 . The regenerative de-acid apparatus for inorganic acidic gas as claimed in  claim 5 , wherein the washing solution supply unit provides de-ionized water, pure water processed by reverse osmosis, distilled water, tap water, or mixed solution of any two of the aforementioned waters.  
     
     
         10 . The regenerative de-acid apparatus for inorganic acidic gas as claimed in  claim 5 , wherein the said gas inlet comprises a gate that is in a closed status when the washing solution supply unit is washing the said adsorbent.  
     
     
         11 . The regenerative de-acid apparatus for inorganic acidic gas as claimed in  claim 5 , further comprising a gate positioned between the said gas inlet and the adsorbent bed, the said gate is in a closed status when the washing solution unit is washing the said adsorbent.  
     
     
         12 . A regenerative de-acid system for inorganic acidic gas, comprising: 
 a piping having plurality of branch pipe each with an opening; and    a plurality of regenerative de-acid apparatuses for inorganic acidic gas, wherein each regenerative de-acid apparatus comprises:    a tank having an gas inlet and an exhaust outlet;    at least one adsorbent bed, which is received inside the tank and includes an adsorbent;    at least one alkaline solution supply unit, which is received inside the tank and provides at least one alkaline solution to the at least one adsorbent bed; and    at least one washing solution supply unit, which is received inside the tank and provides a solution for washing the at least one adsorbent;    wherein the alkaline solution supply unit is positioned between the adsorbent bed and the gas inlet; and    each gas inlet of the tank connects to a respective opening of the branch pipe.    
     
     
         13 . The regenerative de-acid apparatus for inorganic acidic gas as claimed in  claim 12 , wherein the said alkaline solution is potassium hydroxide solution, sodium hydroxide solution or their mixture.  
     
     
         14 . The regenerative de-acid apparatus for inorganic acidic gas as claimed in  claim 12 , wherein the said at least one adsorbent is spherical active carbon, granular active carbon, pulverized active carbon, active carbon fabric, zeolite adsorbent, or mixtures of any two of the aforementioned materials with adsorbability.  
     
     
         15 . The regenerative de-acid apparatus for inorganic acidic gas as claimed in  claim 12 , wherein the said gas inlet comprises a gate in a closed status when the washing solution supply unit is washing the said adsorbent.  
     
     
         16 . A method for processing inorganic acidic gas, comprising the following steps: 
 (a) forming a mixture of inorganic acidic gas and a nebulized alkaline solution wherein the nebulized alkaline solution can be produced continuously or periodically;    (b) forcing the mixture to pass through an adsorbent bed, wherein the said adsorbent is washed by water, or sprayed or immersed by alkaline solution; and    (c) releasing the treated gas.    
     
     
         17 . The method for processing inorganic acidic gas as claimed in  claim 16 , further comprising: 
 (d) repeating step (b) and (c); and    (e) washing the said adsorbent with a washing solution; and spraying or immersing a nebulized alkaline solution to the said adsorbent.    
     
     
         18 . The method for processing inorganic acidic gas as claimed in  claim 15 , wherein the inorganic acidic gas is hydrofluoric acid, hydrochloric acid, nitric acid, sulfuric acid, phosphoric acid, or mixtures of any two of the aforementioned inorganic acidic gases.  
     
     
         19 . The method for processing inorganic acidic gas as claimed in  claim 16 , wherein the alkaline solution is potassium hydroxide solution, sodium hydroxide solution, or their mixture.  
     
     
         20 . The method for processing inorganic acidic gas as claimed in  claim 16 , wherein the adsorbent is spherical active carbon, granular active carbon, pulverized active carbon, active carbon fabric, zeolite adsorbent, or mixtures of any two of the aforementioned materials with adsorbability.